Gestures are used in many fields, from bartering to transportation to music to computing. In bartering, transportation and music, gestures usually convey information directly from one human to another. In the field of computing, a gesture may be part of a human-machine command interface, protocol, etc. While gestures are often associated with bodily signs or movements, regardless of the field, a person may possibly make a gesture using a tool, an instrument, etc. As examples, consider a conductor with a baton, an air marshaller with lighted wands, or a stock trader with a colored card.
In the field of computing, gestures have also become associated with so-called touch or multi-touch sensors that require physical contact or close-contact (e.g., close EM field sensors) with a generally flat sensing surface. As to non-touch or non-contact gestures, a camera may be implemented along with associated circuitry to acquire, stream and analyze video data for purposes of gesture detection. When compared to contact-based systems, non-contact systems can provide some additional freedom, for example, by allowing a person to be some distance from a camera, a computing system, etc.
Where video data are relied upon for gesture detection, such data may be streamed according to a particular format, such as the Common Intermediate Format (CIF, H.261 standard), which specifies a video resolution of 352×240 pixels (width×height) with a frame rate of 30000/1001 (about 30 fps) and color encoding as YCbCr 4:2:0; a Video Graphics Array (VGA) “format”, which specifies a resolution of 640×480 pixels (width×height) and a frame rate of about 15 fps; or other format. Whether video is streamed according to CIF, VGA or other format, such streaming and analysis of video data can place substantial demands on a computing system. Where such a computing system has only on/off control for non-contact gesturing, performance may differ substantially between on and off states. Further, in an off state, it is not possible to turn the gesturing feature on by using a non-contact gesture. Given such constraints, a user may simply leave the gesturing feature in an on state and accept degraded performance or simply leave the gesturing feature in an off state and not use it.
As described herein, various technologies, techniques, etc., can optionally provide for gesture detection with reduced resource demands, which, in turn, may, for example, improve computing performance, user experience, etc.